In applicant's co-pending application, Ser. No. 202,322, applicant disclosed an apparatus for automatically stunning animals to be slaughtered. In the preferred embodiment of the illustrated apparatus, two V-shaped restrainers are used for transporting the animals into contact with stunning electrodes. The animals are first held in a slow moving V-shaped restrainer. The animals are then transferred to a faster moving V-shaped restrainer which moves the animals into contact with stunning electrodes. The faster moving second restrainer insures that the animals will not be touching each other when they are brought into contact with the stunning electrodes.
The transportation of animals in a V-shaped restrainer presents problems that are not involved in the transportation of objects such as bundles of newspapers, cans, jars, boxes, etc., on a flat conveyor belt. Animals that are supported in a V-shaped restrainer are wedged between the opposite operating surfaces of the V-shaped restrainer or conveyor means so that the animal's skin is pressed against the conveyor plates of the restrainer. An animal's hair and hide can become caught in the gaps between adjacent links of the conveyor. As the conveyor plates move around the reversing wheel, the gaps between the plates first open, and then close. That is, the abutting edges of the plates move apart when the plates move out of the plane of the operation surface and begin to move around the reversing wheel. The abutting edges then move together again when the plates return around the reversing wheel to the plane of the operating surface. The skin of the animal can be pinched and damaged by the closing gaps.
In addition, an animal's hide, hair and legs can become caught in the gap between the oppositely moving belts where a first restrainer meets a second restrainer. For example, at the transition area where the exit of the first restrainer meets the entrance of the second restrainer, the opening gap between adjacent plates of the first restrainer's conveyor belts may grip the leg of an animal and move it into the gap between the adjacent reversing wheels of the first restrainer and the second restrainer. The animal's leg may then be caught by the closing gap between adjacent plates of the second restrainer's conveyor belts which are moving in the opposite direction. The gap between the adjacent plates can close with enough excruciating force to break the animal's leg or severely damage it.
When an animal's hide or hair is caught in the gaps between adjacent links of a conveyor belt, the animal can be agitated as the gaps close and the skin of the animal is pinched and damaged. It is believed that this pinching action may inflict excruciating pain on the animal. The animals often sense that something is about to happen and will squirm to try to escape from the V-shaped restrainer. The animal's actions may cause it to be wedged into the V-shaped restrainer even tighter. This increases the likelihood that the animal's skin will be pinched or the animal's leg will be caught, thereby increasing the animal's agitation.
In the environment of a stunning apparatus, this agitation is undesirable. Applicant has recognized that the agitation of the animal tends to raise the pH value of the meat which will lower the quality of the meat that is produced when the animal is slaughtered. Conventional conveyor systems fail to recognize this problem.